This invention basically relates to an apparatus and method for cutting deep-frozen foodstuff in the form of square bodies into a plurality of smaller square units by means of a multi-blade circular saw.
More specifically, the present invention relates to an apparatus for cutting deep-frozen foodstuff, in particular fish, in the form of square bodies such as plates into a plurality of smaller square units such as small rods, comprising a table on which the square bodies are shiftable by means of a conveyor means, a circular saw whose shaft is provided with a plurality of blades which are arranged in the moving path of the square bodies and which are clamped between stiffening disks, with the diameter of said the blades being large with respect to the thickness of the square bodies, as well as hold-down rolls engaging the upper side of the square bodies, in particular pressure rolls.
The invention further relates to a method for cutting deep-frozen foodstuff, in particular meat, fish and vegetables, in the form of square bodies, such as plates into smaller units, such as small rods, using a circular saw comprising one or several saw blades arranged in parallel adjacent relationship in front of which each body is shiftable in the forward direction on a table during the cutting operation.
Some foodstuff, such as fish, is deep frozen into blocks and then cut progressively into smaller square units, such as bars, plates and small rods. It is usual to use belt and circular saws for this purpose. For cutting the square plates into a plurality of square rods, devices of the above mentioned type are used.
In a prior apparatus of the above mentioned type (GB-PS No. 949 495), several circular saw blades are provided and arranged in parallel relationship to each other on a common shaft with their drive below the table on which the plates are shifted. In the table, parallel slots are provided through which the circular saw blades protrude. Since the producer wants to cut as many small rods as possible from the block, he will try to respect the prescribed minimum weight with as little loss as possible. This is only possible when the parts are cut into a precise square form, which requires stiff saw blades. However, the stiffness of a saw blade depends on its thickness. Consequently, a minimum thickness of the saw blades, the periphal edges of which are generally equipped with diamond chips, should be maintained. In an apparatus of the above mentioned type, circular saw blades are used which have a diameter of 125 mm and a thickness of 0.8 to 0.95 mm at the periphery.
Such devices present a number of drawbacks: When cutting with such thick saw blades, an important part of the foodstuff is chipped and is lost in weight if appropriate countermeasures are not taken. One of these prior measures consists of providing rollers which are disposed above the plates transported on the table and which collect a part of the chipped foodstuff centrifuged against them by the saw blades and convey the chipped foodstuff back to the surface of the plates cut into rods. This permits a reduction of the cutting loss. But a big part of the cut foodstuff goes under the table and is lost. Another drawback of prior devices is the output which is presently no longer sufficient. Presently, outputs are required of at least 100 cycles (plates to be cut) per minute. Such an output requires a 30 kw-motor for a saw of the above mentioned type with 20 to 24 saw blades making 8,000 revs per minute. For such a cutting performance of the prior device, there is produced an even bigger cutting loss, and furthermore there is also produced heat during the cutting operation which has to be compensated later by renewed freezing.